CHAP, XII. §.rT. IN FRUITS AND TUBERS. 177 



observed with the galvanometer may, in the majority 

 of instances, be due to ordinary electro-chemical 

 actions, but in some instances the effect cannot be 

 referred to these actions, but may be referred to the 

 organic changes which occur in the roots during 

 vegetation. 



M, That with the petals of flowers slight currents 

 were obtained ; and, 



ith, In fruits and tubers powerful currents may be 

 occasionally obtained, but these efi'ects are evidently 

 secondary results, due to the reaction of the different 

 vegetable juices upon each other. 



